diff --git a/frontend/service.go b/frontend/service.go
index 023a171..397ec1f 100644
--- a/frontend/service.go
+++ b/frontend/service.go
@@ -1,3 +1,4 @@
+// Package frontend implements the gRPC handlers called by the wallets.
 package frontend
 
 import (
diff --git a/walletrpc/service.proto b/walletrpc/service.proto
index 3a1cd62..43788c9 100644
--- a/walletrpc/service.proto
+++ b/walletrpc/service.proto
@@ -74,6 +74,14 @@ message TransparentAddressBlockFilter {
     BlockRange range = 2;
 }
 
+message Balance {
+    int64 valueZat = 1;
+}
+
+message Exclude {
+    repeated bytes txid = 1;
+}
+
 service CompactTxStreamer {
     // Compact Blocks
     rpc GetLatestBlock(ChainSpec) returns (BlockID) {}